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[dinosaur] Late Cretaceous dinosaurs and plants buried in Arctic Kakanaut River basin + pterosaurs





Ben Creisler
bcreisler@gmail.com


Two relatively recent papers translated from Russian journals and not yet mentioned:

S. V. Shczepetov & A. B. Herman (2017)
The formation conditions of the burial site of Late Cretaceous dinosaurs and plants in the Kakanaut River basin (Koryak Highlands, Northeastern Asia).
Stratigraphy and Geological Correlation 25(4): 400–418
DOI: https://doi.org/10.1134/S0869593817040050
https://link.springer.com/article/10.1134/S0869593817040050



The stratigraphic position of layers containing plant and animal remains in the Koryak Highlands (Northeast Asia) is under discussion. Their age is defined as late Campanian–early Maastrichtian. Plant-bearing and bone-bearing rocks represent cemented basaltic tephra. The former contain a small amount of xenogenic material and slightly rounded volcaniclastic material, which indicates its insignificant transportation. Ash particles in bone-bearing rocks are even less rounded. Among them, there are no rock fragments of other composition. Large bones and their fragments, as xenoliths, are chaotically distributed in the rock matrix as if floating in mass of ash material. This burial site was probably formed in a continental environment as a result of the gravitational and eolian transportation of the terrigenous material. The burial of small dinosaur bones and teeth occurred during the deposition of a small stream of a semiliquid water-ash mixture. This work presents a possible mechanism of the formation of burial sites, taking into consideration proposed conditions of the life and reproduction of dinosaurs in the Late Mesozoic Arctic.


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A. V. Koroljov (2017)
Pterosaur flight.
Biology Bulletin Reviews 7(3): 179–228
DOI:  https://doi.org/10.1134/S2079086417030045
https://link.springer.com/article/10.1134/S2079086417030045



There are three known vertebrate groups whose representatives can actively fly: birds, bats, and pterosaurs. Among them, birds are of greatest interest for biologists and engineers. It is the flight of birds that serves as a reference basis for other groups in the studyi or reconstruction the flight of vertebrates. However, whereas the aerodynamic principles are common for all groups due to the environmental uniformity, the biomechanical means of flying depend on the morphological wing features of each of these groups due to their individual evolutionary prehistory. In addition, we can directly observe the flight of birds and bats and compare our assumptions with the actual state, while the study of pterosaurs does not provide this opportunity and allows reconstruction of the flight principles of this group only on the basis of paleontological data on the morphological features of their wing and evolution.



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